Windup chuck



Ogt. 7, 1969 A. 1.. EWING 3, 7

WINDUP CHUCK Filed Dec. 11. 1967 3 Sheets-Sheet 1 INVENTOR ALVlN L. EWIN G i I ri /7M I ATTORNEY 3 Sheets-Sheet :3

x 2 a 2 s 2 2 m .7 2 z 2 z A. EWING WINDUP 0110014 I III I I I I I II IIII III I I II I Oct. 7, 1969 Filed Dec. 11. 1967 O. 7, 1969 Ewme 3,471,095

WINDUP CHUCK Filed Dec. 11. 1967 l a Sheets-Sheet 3 FIG-5 mvsmon ALVIN L. EWING ATTORNEY United States Patent O US. Cl. 24246.5 4 Claims ABSTRACT OF THE DISCLOSURE A windup chuck comprising a cylindrical sleeve rotatably mounted on a fixed spindle, said sleeve being adapted to receive drive rings with associated retainer and spacer means and a bobbin tube; said rings having a peripheral surface of a diameter slightly less than the inside diameter of said bobbin tube, said peripheral surface being adapted to receive said tube and having radially spaced raised portions of such a degree that the diameter of a circle circumscribing the raised portions is slightly greater than the inside diameter of said bobbin tube to provide initial gripping force and to center the tube on said chuck, said rings being of an elastomeric material capable' of radial expansion under the action of centrifugal forces and having a substantial coefiicient of friction with said tube. Also disclosed are means for adjusting the initialgripping force of the rings on the tube and means for preventing the rings from free-floating within the retainer means while maintaining concentricity.

BACKGROUND OF THE INVENTION Field of the invention This invention relates to a rotatable chuck for tubular cores which is useful for winding thread and the like into packages and more particularly to improvements in the chuck described by Ewing et al. in US. Patent 3,272,447.

Description of the prior art The final step in the production of textile fibers often involves winding them on bobbin tubes which are supported on rotatable chucks driven by rolling contact with a drive roll. With the increasing speeds now attainable in modern textile plants, problems have arisen in designing commercially suitable chucks. It is generally accepted that these chucks should have the following attributes: (a) they should be self-centering; (b) they should permit easy placement and removal of the tube on which the yarn is wound; (c) they should insure firm gripping of the tube under all winding conditions, and (d) they should maintain concentricity of the core both at startup and at high speeds while keeping the winding assembly in balance.

The chuck described in the above cited Ewing et al. patent was designed to meet all these requirements, its main features being three difierent types of rings with each fulfilling a different function. A first type of ring, made of fairly rigid material, served to center the core on the chuck. A second type of ring, made of compressible material, served to initially engage the core and provide a gripping action at low speeds. A third type of ring, made from material capable of radial expansion under the action of centrifugal forces, served to tightly grip the core at high speeds.

In operating with the chuck described above, maintenance problems have arisen which are mainly associated with the first type of ring. It has been found that placing and removing the bobbins caused breakage or bending of the ring edges that serve to center the bobbins. It was thus necessary to replace the centering rings fairly frequently in order to maintain the chuck in good operating "ice condition. Another problem encountered was that the compressible rings which served to initially engage the bobbin were subject to permanent set, thus causing the rings to lose their holding power, thereby necessitating their frequent replacement. Furthermore, the use of three diflerent types of rings somewhat complicates fabrication of this chuck.

The present invention provides a rotatable chuck meeting the requirements mentioned above, while virtually eliminating the maintenance problems. It also provides a chuck of simplified and improved design in which the three different types of rings performing different functions are replaced by a single type of ring performing multiple functions. Still another provision is to provide such a chuck wherein the rings are prevented from free floating. A further advantage is such a chuck with means for adjusting the initial frictional force holding the tubular core.

SUMMARY OF THE INVENTION The present invention is a windup chuck comprising a cylindrical sleeve rotatably mounted on a fixed spindle,

said sleeve being adapted to receive drive rings with associated retainer and spacer means and a bobbin tube; said rings having a peripheral surface of a diameter slightly less than the inside diameter of said bobbin tube, said peripheral surface being adapted to receive said tube and having radially spaced raised portions of such a degree that the diameter of a circle circumscribing the raised portions is slightly greater than the inside diameter of said bobbin tube to provide initial gripping force and to center the tube on said chuck, said rings being of an elastomeric material capable of radial expansion under the action of centrifugal forces and having a substantial coefficient of friction with said tube.

More particularly the present invention provides a chuck adapted to receive a tubular bobbin, the chuck comprising a fixed spindle, a tubular housing rotatably mounted on the spindle, means for holding the housing on the spindle and a number of identical rings made from a rubber-like material mounted on the housing, retaining means for the rings and tightening means to hold the assembly in place. These rings, whose diameter is slightly smaller than the inside diameter of the bobbin and which are capable of radial expansion under the action of centrifugal forces, have a number of raised sections equally spaced around their circumference, the diameter of a circle circumscribing these raised sections being slightly larger than the inside diameter of the bobbin tube. The ring retainers are so constructed that tightening or loosening the assembly will increase or decrease the diameter of this circumscribing circle thus allowing adjustment of the initial holding force.

BRIEF DESCRIPTION OF DRAWINGS The invention will be better understood from the following description made with reference to the attached drawings in which:

FIGURE 1 is a fragmentary end view of a traverse winding apparatus incorporating the chuck construction of the present invention;

FIGURE 2 is a longitudinal section of the chuck with the bobbin tube in place;

FIGURE 3 is a side elevation of a multiple-function rubber ring of this invention;

FIGURE 4 is another view of the rubber ring taken at right angles to the view shown in FIGURE 3;

FIGURE 5 is a side elevation of one type of ring retainer of this invention;

FIGURE 6 is a cross section through this retainer taken along the line VIVI of FIGURE 5;

3 FIGURE 7 is a side elevation of another type of ring retainer of this invention; and

FIGURE 8 is a cross section along the line VIIIVI]1 of FIGURE 7.

DESCRIPTION OF THE PREFERRED EMBODIMENTS The winding apparatus shown in FIGURE 1 includes a drive roll 1 and a swing arm 3 on which a chuck 5 is freely rotatable. The chuck has a bobbin tube 7 telescoped thereon and is driven by rolling engagement with the drive roll. A filamentary structure 9 is thus wound onto each bobbin to form a yarn package.

Referring now to FIGURE 2, the chuck of the invention has an arrangement generally similar to that desscribed in Ewing et al. US. Patent 3,272,447 dated Sept. 13, 1966. It comprises a fixed spindle 12 and a housing 11 rotatably mounted on the spindle by means of bearings 13. The bearings are held in place by tubular bearing spacer 14, spindle shoulder 15, and lock nut 16. Housing 11 is held in position by threaded retainer ring 17. Rubber rings 18, having raised portions 19, are mounted on the housing 11 and held in place by means of two types of retainers denoted as 20 and 21. A clearance is provided between the rings and retainers to allow for centrifugal expansion of the rings. The retainers 21 are held in spaced relationship by tubular spacers 22 and 23. The entire assembly is keyed together and is driven from both the left hand side of the chuck and the right hand side by means of retainers 20. The left hand side retainer is keyed to the housing 11 by means of pins 29 fitting into appropriate holes drilled in the housing. The right hand side retainer is similarly attached by pins 29 inserted in the washer 31. The entire assembly is held in place by lock nut 24. A clearance is provided between the retainers 20, 21 and rubber rings 18 to allow radial expansion of the rings. A circumferential stop 25 extending radially is provided on the tubular housing 11 to abut one end of the tubular bobbin 26 and provide an initial driving surface for the drive roll to bear on until some yarn has been wound upon the bobbin tube, thereby protecting the bobbin.

FIGURES 3 and 4 show details of the rubber rings 18 which has three projections 19 radially spaced 120 from one another around the circumference of the ring. The rings are provided with shoulders or lips 27 also having three raised portions 30. Holes 28 are drilled partway through the rings and receive pins 32 (FIGURES 5, 6, 7, and 8) of the retainers 20 and 21. These pins function to key rings 18 to the housing 11 and prevent relative motion of the rings about the housing. As shown in FIG- URE 2, adjacent rubber rings are mounted so that raised portions 19 of one ring are displaced by about 60 from the raised portions 19 of the other ring.

The height of raised portions 19 above the circumference of the ring 18 and the number of these raised portions are important design characteristics for ensuring good operability of the chuck of this invention and have a direct relation to the ease of inspection of an empty core on the chuck and removal of a full yarn package. It is preferred that they be relatively few in number and that their height be such that a circle circumscribing these raised sections will have a diameter about 10-30 thousandths of an inch larger than the inside diameter of bobbin 25. As will be described in more detail below, an important improvement in the present chuck is the provision of means for adjusting this diameter and hence the initial holding force on the bobbin. Rings 18 are preferably constructed of relatively high density elastomeric material such as synthetic or natural rubber. Materials having Durometer hardness in the range -70 and a specific gravity of about 22.5 have been found suitable for this purpose.

The raised portions 30 on lips 27 of rings 18 constitute another improvement in the chuck of this invention.

These raised portions maintain continuous contact between the rings 18 and the retainers 20' and 21 when the chuck accelerates from rest to operating speed. This acts to maintain the bobbin concentric with the axis. In addition, they prevent the rings from free-floating when they expand due to centrifugal forces and thus prevent excessive pand due to centrifugal forces and thus prevent excessive vibrations to be encountered when the chuck-bobbin assembly passes thorugh a critical speed.

FIGURES 5 and 6 are views of ring retainers 20 while FIGURES 7 and 8 are views of ring retainers 21. Retainers 21 (two of which are provided) differ in design from retainers 20 because they must cooperate with the tubular spacers 22 and 23. As shown, all the retainers are provided with three small projections 33 which hold the retainers apart and prevent them from pressing against the rubber rings 18. These projections, together with the fact that the retainers are not as thick as therings are, provide a means for controlling the initial gripping force on the bobbin. If the bobbin is found to be too loose on the chuck, .tightening the lock nut 24 causes these projections to deform with the space between the retainers decreasing thereby causing the rubber rings 18 to expand radially thus increasing the force of contact between the bobbin and raised portions 19 on rubber rings 18. It has been found that a suitable initial gripping force is obtained when the force required to pull the empty bobbin from the chuck is within the range of 35-40 lbs.

The ring retainers 20 and 21 can be made from metal but are preferably and more economically constructed from a palstic material such as 66 nylon. Tubular spacers 22 and 23 can also be fabricated from metal but are more economically fabricated from resin impregnated paper or similar laminated materials. Housing 11, spindle 12 and bearing spacers 14 are suitably fabricated from steel or other appropriate metal. Circumferential stop 25 is preferably made of slightly larger diameter than the diameter of the bobbin 25 to prevent the drive roller from contacting the empty bobbin at the beginning of the winding operation. Circumferential stop 25 may be constructed in a single piece or as illustrated in FIGURE 2 of two patrs comprising a steel ring which is press fitted onto the housing 11 and an outer ring of laminated plastic material. A suitable material for the outer part of the stop is fabric-reinforced phenolic resin.

In operation, the bobbin 26 is placed over the chuck and is centered by the raised portions 19 of the rings 18. These raised portions 19 also provide the relatively low gripping force required at low speed. Initially, the retainers 20 and 21 bear upon raised portions 30 of lips 27 on rings 18. As the rotational speed of the chuck-bobbin assembly increases, the surfaces of rings 18 expand radially to come into contact with the bobbin 26, while the surfaces of lips 27 also expand and come in contact with retainers 20 and 21, thus providing gripping means adapted to secure the bobbin while it is rotating at high speeds.

The chuck of this invention thus meets all the requirements for an efficient high speed winding operation, while eliminating the maintenance problems associated with the chuck described in the Ewing et al. patent (US. 3,272,447). The number of different parts is reduced and it is thus simpler and more economical to manufacture. It provides for easy placement and removal of the bobbins and they are held firmly in place during the entire winding ing a peripheral surface of a diameter slighlty less than the inside diameter of said bobbin tube, said peripheral surface being adapted to receive said tube and having radially spaced raised portions of such a degree that the diameter of a circle circumscribing the raised portions is slightly greater than the inside diameter of said bobbin tube to provide initial gripping force and to center the tube on said chuck, said rings being of an elastomeric material capable of radial expansion under the action of centrifugal forces and having a substantial coeflicient of friction with said tube.

V 2. The chuck as defined in claim 1 wherein each side of said rings has a radial lip of a lesser diameter than said ringpheripheral surface and is adapted to receive said retainer means, the radial surface of said lip being spaced slightly from said retainer means to allow for radial expansion and said lip having radially spaced raised portions to engage said retainer means to prevent free-floating of the rings and to maintain concentricity.

3. The chuck as defined in claim 1 wherein said retainer means has adujstment means to regulate the longitudinal axial force exerted against said rings.

6 4. The chuck as defined in claim 1 wherein said rings are made of an elastomeric material having a Durometer hardness within the range of about to about and a specific gravity of about 2 to 2.5.

References Cited UNITED STATES PATENTS 2,219,124 10/1940 Bandy 24272 2,620,140 12/1952 Naegeli 24246.6 3,253,323 5/1966 Saueressig 24272 XR 3,272,447 9/1966 Ewing et al. 24246.5 3,335,971 8/1967 Richter 24246.5

FOREIGN PATENTS 763,507 5/ 1934 France.

MERVIN STEIN, Primary Examiner 20 WERNER H. SCHROEDER, Assistant Examiner 

